Streaming multimedia is multimedia that is constantly received by, and normally displayed to, the end-user while it is being delivered by the provider. The Real-time Transport Protocol (or RTP) defines a standardized packet format for delivering audio and video over the Internet. It was developed by the Audio-Video Transport Working Group of the IETF and first published in 1996 as RFC 1889, which was made obsolete in 2003 by RFC 3550. It is frequently used in streaming media systems in conjunction with the Real Time Streaming Protocol (RTSP), developed by the IETF and created in 1998 as RFC 2326. RTSP is a protocol that allows a client to remotely control a streaming media server, issuing VCR-like commands such as “play” and “pause.” The Real-time Transport Protocol (RTP) and the Real-time Transport Control Protocol (RTCP) are commonly used together. RTP is used to transmit data (e.g. audio and video) and RTCP is used to monitor Quality of Service (QoS).